Vented curl for aerosol dome

ABSTRACT

An aerosol dome having a lower end adapted to be attached to the upper end of a container and having an upper open end surrounded by an outwardly turned wall. The outwardly turned wall has a free edge and an adjacent end portion in overlapping relation with an adjacent outer surface of the aerosol dome to define a curl with an enclosed area having an internal radius. A major circumferential portion of the curl defined by the wall has a substantially constant or fixed internal radius which locates the free edge in contacting engagement with the outer surface of the dome and at least one selected circumferential portion of the curl has a radius at the free edge which is less than the fixed internal radius to space that portion of the free edge from the outer surface and provide a vent opening for the internal area of the curl.

United States Patent Miller et al. [451 July 25, 1972 [54] VENTED CURLFOR AEROSOL DOME Primary Examiner-George E. Lowrance [72] Inventors:Stanley J. Miller; James P. Davidson, both Anomey Roben Dqheny ofChicago, Ill. [57 1 ABSTRACT [73 Assignee: Nuuonal can Comm-aim ChlcagoAn aerosol dome having a lower end adapted to be attached to [22] Filed:April 9, 1970 the upper end of a container and having an upper open endsurrounded by an outwardly turned wall. The outwardly PP 26,872 turnedwall has a free edge and an adjacent end portion in overlapping relationwith an adjacent outer surface of the 52 0.5. CI ..220/67 220/74 222 182define 8 an enclosed area having [51] In 3'65! 7/42 internal radius. Amajor circumferential portion of the curl [58] Fieid 82 402 l defined bythe wall has a substantially constant or fixed inter- 402 2 5 402 24 nalradius which locates the free edge in contacting engagement with theouter surface of the dome and at least one selected circumferentialportion of the curl has a radius at the [56] References Cited free edgewhich is less than the fixed internal radius to space UNITED STATESPATENTS that portion of the free edge from the outer surface and providea vent opening for the internal area of the curl. 3,468,452 9/1969Khoury ..220/67 7 Claims, 5 Drawing Figures VENTED CURL FOR AEROSOL DOMEBACKGROUND OF THE INVENTION The present invention relates generally tocontainer ends and more particularly to an improved aerosol dome havinga vented bead.

In the formation of aerosol containers, it is customary to separatelyform, what is commonly referred to as, an aerosol dome and attach oneend of the aerosol dome to the main body of the container. Generally,the aerosol dome has an opening formed at the upper end thereof, whichhas a diameter less than the diameter of the main body of the container.The upper opening is surrounded by a bead or curl which is formed by anintegral outwardly turned wall that is rolled to a substantiallycircular cross-sectional configuration to form a closed bead.

The upper open end is capable of receiving a mounting cup supporting avalve mechanism and the surrounding bead or curl serves as a support fora channel member on the upper end of the mounting cup which is crimpedto the container end. In some constructions, the free edge and anadjacent end portion of the outwardly turned wall are placed inoverlapping contacting relationship to the adjacent outer surface of thedome to rigidify the entire structure.

In many instances, the aerosol container is filled by forcing propellantand product between the adjacent surfaces of the mounting cup and theaerosol dome before the mounting cup is crimped to the bead of the dome.In such a filling operating one practice, which has become customary, isto loosely insert the mounting cup with the valve mechanism securedtherein into the open end of the container and, thereafter, place acharging head into sealing engagement with the surface of the aerosoldome at a point spaced from the bead. After a vacuum has been producedwithin the container, the high pressure low temperature propellant, aswell as product, both of which are in a liquid state, areforced betweenthe upper rim of the mounting cup and the adjacent bead on the upper endof the aerosol dome. After the container has been filled to the desiredlevel, the mounting cup is crimped and sealed within the containeropening before the charging head is removed.

It has been found that during such a filling operation, some of thepropellant and product may be forced into the closed internal area ofthe bead or curl. Thereafter, the propellant, which is in a gaseousstate at room temperature and substantially atmospheric pressure, willtend to escape while the filled containers are checked for leakers.Since, it is customary to immerse the entire container into a heatedwater bathto detect leakers," the escape of the gaseous propellant fromthe internal area of the bead will produce bubbles in the bath resultingin the interpretation that the container is a leaker.

Another problem encountered in having propellant and product trapped inthe internal area of the bead is that the product, which is in liquidform at room temperature, will tend to seep from the internal area ofthe bead while the container is on display. Again, this seepage ofproduct from the internal area of the bead will be interpreted to beleakage from the internal area of the container and will result inhaving the retailer return the container as being defective or willcause the purchaser to refuse to buy the product because of theunsightly appearance on the surface of the container dome.

Thus, there is an urgent need for a simple and effective method forpreventing the trapping of propellant and product in the internal areaof the bead while still maintaining a bead of sufficient integrity toperform its intended function.

BRIEF SUMMARY OF THE PRESENT INVENTION The present inventioncontemplates the formation of a container end of the type having aperipheral bead or curl surrounding an open end with the bead beingdefined by an outwardly turned wall having a free end portion which isin overlapping relationship with the adjacent outer surface of thecontainer end. The overlapping relation of the outwardly turned wall andthe adjacent outer surface produces a substantially closed area having asubstantially constant or fixed internal radius.

The present invention contemplates that the major portion of the bead beformed to have a substantially constant or fixed internal radius whichwill locate the free edge of the overlapping portion in contactingengagement with the outer surface of the container end with at least oneselected circumferential portion of the bead having a radius at the freeedge which is less than the fixed radius to thereby space the free edgefrom the outer surface and provide a vent opening for the internal areaof the bead. Stated another way, a minor circumferential portion of thebead has a spiral configuration commencing with a minimum radius at thefree edge with the radius increasing to substantially the fixed radiusof the remainder of the bead at the point spaced from the contactingengagement of the wall With the adjacent surface.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS DETAILEDDESCRIPTION While this invention is susceptible of embodiment in manydifferent forms, there is shown in the drawings and will herein bedescribed in detail, one specific embodiment, with the understandingthat the present disclosure is to be considered as an exemplification ofthe principles of the invention and is not intended to limit theinvention to the embodiment illustrated.

FIG. 1 of the drawings discloses an upper end of an aerosol container 10including a main body 12 of the container and an end portion aerosoldome 14. The lower end of the aerosol dome 14 is suitably secured to theupper end of the cylindrical body 12 through a sealed joint 16, whichmay be in the form of a commercially known double seam.

The upper end of the dome 14 has an opening 18 formed therein which issurrounded by a bead 20. In its completely assembled condition, theaerosol container 10 has a mounting cup 22 received in the opening 18with a downwardly opening annular channel 23 crimped at 24, in sealingengagement with the bead 20 with the mounting cup 22 supporting a valvemechanism 26.

As was indicated above, when utilizing under-the-cap" filling, it iscustomary to loosely insert the mounting cup 22 into the opening '18 andthereafter to telescope a charging head over the valve mechanism withthe charging head being placed in contacting engagement with the outerperipheral surface of the dome 14 at a point outwardly spaced from thebead 20. A vacuum is then produced within the container and propellantand product are forced into the container between the adjacent surfacesof the upper end of the aerosol dome and the upper end of the mountingcup. AT the higher pressure, both the product and the propellant are inliquid form and will tend to be forced and trapped into the internalarea of the closed bead 20. This propellant and product many times willremain trapped within the internal area of the bead 20 after themounting cup 22 has been crimped and sealed to the aerosol dome l4 andthe changing head has been removed.

This trapped propellant and/or product within the closed area of thebead is undesirable.

According to the present invention, the above mentioned problems arealleviated by venting the internal area of the bead in a simple andeffective manner. Thus, the present invention contemplates rollingselected circumferentially spaced portions to a cross-sectionalconfiguration in which a first segment adjacent the free edge of theoutwArdly turned wall is of substantial spiral configuration with theminimum radius of the spiral being located at the free edge. Secondsegments, or the remainder of the selected circumferentially spacedportions, each are rolled to a substantially constant or fixed radiuswhich is equal to the constant or fixed internal radius of the remainderof the bead. With such an arrangement, the free edge of each of theselected portions is spaced from the adjacent outer surface to vent theinternal area of the bead while the remainder of the free edge and theadjacent overlapping end portion of the wall are in contactingengagement with the outer surface to maintain the necessary integrity inthe bead 20.

As is more clearly shown in FIGS. 2, 3 and 4, the major circumferentialportion of the bead 20 is defined by an integral outwardly turned wall30 which has a free edge 32 and an ad jacent end portion 34 inoverlapping relationship with an adjacent outer surface 36 of the mainbody portion of the dome 14 to define a closed area 38. As shown inFIGS. 2 and 3, the major circumferential portion of the bead 20 has aninternal area 38 which is of a substantially constant cross-sectionalconfigurAtion and has a fixed or constant internal radius. However,selected circumferential portions of the wall 30 have a first segment,as shown in FIG. 4, OF a spiral cross-sectional figuration with theminimum radius of the spiral seg ment being at the free edge 32 So as tospace the free edge 32 as well as the overlapping end portion 34 fromthe adjacent surface 36 F the dome 14. The first segment encompassesapproximately one-fourth of the selected circumferential portion whilethe remaining or second segment of the selected circumferential portionshave a substantially fixed radius which is equal to the substantiallyconstant internal radius of the major portion of the bead.

While not specifically necessary to the present invention, it iscontemplated that selected circumferential portions be at diametricallyopposed points relative to the open end 18 of the dome 14 with each ofthe circumferentially spaced selected portions being divided into firstand second sections 40 and 42 with an intermediate section 44 which hasa cross-sectional configuration corresponding to the cross-sectionalconfiguration of the major portion shown in FIG. 3. By rollingcircumferentially spaced and diametrically opposed pairs of sections tothe reducing internal radius adjacent the free edge, the forcesencountered during such a rolling process will be balanced.

An inspection of FIG. 2 shows that the lower edge of the bead 20 has asubstantially serpentine or sinuous configuration. However, theamplitude of the wave defining the lower edge of the selectedcircumferential portion is extremely small, but is sufficient to placeat least the peak above the remainder of the lower edge of the bead andproduce a small opening between the adjacent outer surface of the dome.

FIG. is a view similar to FIG. 2 but showing a single small openingbeing formed on each half of the bead. It will also be appreciated thatonly one opening for the entire bead is necessary to produce sufficientventing for the entire bead. The cross-sectional configuration of theportion of the bead producing the opening 50in FIG. 5 is substantiallyidentical to that shown in FIGS. 3 and 4.

Thus, it will be appreciated that the present invention provides asimple and effective manner for venting the internal normally closedarea of a bead surrounding an open end of an aerosol dome. Furthermore,the vented bead may readily be formedduring the forming process whichproduces the outwardly curled wall defining the bead.

What is claimed is:

I. In a domed container end of the type having a dome wall and aperipheral vented curl surrounding an open end and formed by anoutwardly turned portion of said wall adjacent a free edge thereof, inwhich said curl defines a closed area havmg an internal radius, theimprovement in said curl comprising: a segment of said outwardly turnedportion adjacent said free edge being overlapped with and in a contouredplane substantially parallel to the adjacent outer surface of said domewall; said overlapping segment being in contacting engagement with saidadjacent outer surface along a major circumferential portion of saidcurl; said internal radius being reduced at at least one selectedcircumferential portion extending from said free edge into said closedarea to provide a vent opening for said curl.

2. The improvement of claim 1, in which a major portion Of the curl atsaid at least one selected circumferential portion has an internalradius equal to the internal radius of said curl along said majorcircumferential portion.

3. The improvement as defined in claim 2, in which the remainder of thecurl at said at least one selected circumferential portion has agradually reducing radiusbetween said major portion of said curl andsaid free edge.

4. In a domed container end of the type having a dome wall and aperipheral vented curl surrounding an open end and formed by anoutwardly turned portion of said wall adjacent a free edge thereof, inwhich said curl defines a closed area having an internal radius, theimprovement in said curl comprising: a segment of said outwardly turnedportion adjacent said free edge being overlapped with and in a contouredplane substantially parallel to the adjacent outer surface of said domewall; said overlapping segment being in contacting engagement with saidadjacent outer surface and said internal radius being substantiallyfixed along a major circumferential portion of said curl; said internalradius at at least one selected circumferential portion being reduced atsaid free edge and increasing at locations away from said free edge tosaid fixed internal radius to form a spiral cross-sectionalconfiguration at said at least one selected circumferential portionwhereby said free edge at said at least one selected circumferentialportion is spaced from said outer surface to place said closed area incommunication with the area surrounding said curl.

5. The improvement of claim 4 in which said at least one selectedcircumferential portion comprises a spaced pair of diametrically opposedsections.

6. In a domed container end of the type having a dome wall and aperipheral vented curl surrounding an open end and formed by anoutwardly turned portion of said wall adjacent a free edge thereof, inwhich said curl defines a closed area having an internal radius, theimprovement in said curl comprising: a segment of said outwardly turnedportion adjacent said free edge being overlapped with and in a contouredplane substantially parallel to the adjacent outer surface of said domewall; a major circumferential portion of said curl having across-sectional configuration with a constant internal radius placingsaid free edge in contact with said outer surface; and at least oneselected circumferential portion having a first segment of spiralcross-section configuration with the minimum radius of said segmentbeing at said free edge and a second segment with a substantially fixedradius equal to said constant internal radius whereby the free edge ofsaid selected circumferential portion is spaced from said outer surfaceto vent the closed area of said curl to the atmosphere.

7. An aerosol dome as defined in claim 6, in which said at least oneselected circumferential portion comprises first and second pairs ofsections, said pairs of sections being in diametrically opposed relationrelative to said open end and each pair having an intermediate sectionof cross-sectional configuration corresponding to said major portion.

1. In a domed container end of the type having a dome wall and aperipheral vented curl surrounding an open end and formed by anoutwardly turned portion of said wall adjacent a free edge thereof, inwhich said curl defines a closed area having an internal radius, theimprovement in said curl comprising: a segment of said outwardly turnedportion adjacent said free edge being overlapped with and in a contouredplane substantially parallel to the adjacent outer surface of said domewall; said overlapping segment being in contacting engagement with saidadjacent outer surface along a major circumferential portion of saidcurl; said internal radius being reduced at at least one selectedcircumferential portion extending from said free edge into said closedarea to provide a vent opening for said curl.
 2. The improvement ofclaim 1, in which a major portion Of the curl at said at least oneselected circumferential portion has an internal radius equal to theinternal radius of said curl along said major circumferential portion.3. The improvement as defined in claim 2, in which the remainder of thecurl at said at least one selected circumferential portion has agradually reducing radius between said major portion of said curl andsaid free edge.
 4. In a domed container end of the type having a domewall and a peripheral vented curl surrounding an open end and formed byan outwardly turned portion of said wall adjacent a free edge thereof,in which said curl defines a closed area having an internal radius, theimprovement in said curl comprising: a segment of said outwardly turnedportion adjacent said free edge being overlapped with and in a contouredplane substantially parallel to the adjacent outer surface of said domewall; said overlapping segment being in contacting engagement with saidadjacent outer surface and said internal radius being substantiallyfixed along a major circumferential portion of said curl; said internalradius at at least one selected circumferential portion being reduced atsaid free edge and increasing at locations away from said free edge tosaid fixed internal radius to form a spiral cross-sectionalconfiguration at said at least one selected circumferential portionwhereby said free edge at said at least one selected circumferentialportion is spaced from said outer surface to place said closed area incommunication with the area surrounding said curl.
 5. The improvement ofclaim 4 in which said at least one selected circumferential portioncomprises a spaced pair of diametrically opposed sections.
 6. In a domedcontainer end of the type having a dome wall and a peripheral ventedcurl surrounding an open end and formed by an outwardly turned portionoF said wall adjacent a free edge thereof, in which said curl defines aclosed area having an internal radius, the improvement in said curlcomprising: a segment of said outwardly turned portion adjacent saidfree edge being overlapped with and in a contoured plane substantiallyparallel to the adjacent outer surface of said dome wall; a majorcircumferential portion of said curl having a cross-sectionalconfiguration with a constant internal radius placing said free edge incontact with said outer surface; and at least one selectedcircumferential portion having a first segment of spiral cross-sectionconfiguration with the minimum radius of said segment being at said freeedge and a second segment with a substantially fixed radius equal tosaid constant internal radius whereby the free edge of said selectedcircumferential portion is spaced from said outer surface to vent theclosed area of said curl to the atmosphere.
 7. An aerosol dome asdefined in claim 6, in which said at least one selected circumferentialportion comprises first and second pairs of sections, said pairs ofsections being in diametrically opposed relation relative to said openend and each pair having an intermediate section of cross-sectionalconfiguration corresponding to said major portion.